Lubricating gun



C. W. HEFNER LUBRICATING GUN Dec. 19, 1933.

Filed Feb. 11, 1933 2 Sheets-Sheet, l

Inventor Dec. 19, 1933.

C. W. HEFNER LUBRICATING GUN Filed Feb.

11, 1933 2 Sheets-Sheet 2 "IIIIIII'I4 a Whi e/Iv r Patented Dec. 19 1933 I W A P ENT- omcs Application February 11, 1933. Serial No 656,334

3 Claims. .(Cl. 221-474) This invention relates to a grease lubricating gunwherein force rather than vacuum is used as the agency for supplying a charge of lubricant to the ejector mechanism of the gun, with the result that a lubricant, heavier than the lubricant now generallyhandled by a grease gun maybe used in connection withthe gun embodying the features of the invention; a uniform quantity of lubricant is delivered at each discharge of the tion, taken in connection with the accompanying drawings wherein: t

Figure lis a top plan view of the gun.

,Figure 2 is a longitudinal sectional view therethrough taken substantiallyonthe line 2-'-2 of Figure 1. r

, Figure 3 is a longitudinal sectional View through a portionof the barrel and-the discharge mechanism embodying the features of the present invention.

Figures 4, 5, 6 and 7 are transverse sectional views taken substantially on the lines 4-4, 55, 6-6 and '77 respectively of Figure 2.

Referring to the drawings by reference numerals it will be seen that the gun embodying the features of the present invention comprises a barrel composed of sections 10, 11, one of which in the present instance, section '10 is cylindrical and provides a reservoir chamber 12, while the other of which, in this instance section 11 provides a charge receiving chamber 13 andhas, at one end, screw threaded engagement with the section 10 as at 14. The section 11 is preferably of the shape shown being provided adjacent its internally threaded end with a conical portion merging into an elongated contracted end portion which in cross section is of the shape clearly suggested in Figure '7. The cylindrical section 10 is opened at each end and for the outer end of the section 10 there is provided a screw cap 15. An apertured partition plate 16 is suitably clamped between the inter-engaged ends of the sections 10, 11 as suggested in Figure 2 and forms a dividing wall between the compartments 12, 13. The aperture in the partition plate 16 serves to establish communication between the reservoir 12 and the charge receiving compartment or chamber 13. Mounted to reciprocate within the chamber 12 for. forcing lubricant from the'chamber 12 into the charge receiving chamber 13 isa piston 17, the same being preferably of the cup-shaped type and is suitably provided on one end of a rod 18 that extends through an opening in the cap 15 and is provided on itsouter end with a handle 19. Arranged in the section 11 of the barrel is a discharge mechanism. The said discharge mechanism comprises an elongated tube 20 slidably operating in a gland structure 21 provided at the free end of the barrel section 11. On the outer end thereof the cylinder 20 is provided with a discharge nozzle 22 while the inner end of the cylinder slidably receives a fixed piston 23 that has a headed end suitably engaged with the partition plate 16 as shown. -Disposed about the piston 23 is a spring 24 that normally retains the cylinder 20 in projected position with reference to the barrelof the gun. Spring 24 as shown is engaged at one end with a head 25 provided on the piston 23, and at its other end the spring is suitably engaged with the inner end of the cylinder 20,

Operating wholly within the chamber 13 is a relatively short cylinder 26 that has one end slidably engaging a fixed piston 2'7 projecting 80. inwardly from the end wallr28 of the chamber 13; and a spring 29 mounted relative to the piston 27l and cylinder 26 substantially in the same manner as the spring 24 is mounted with respect to the cylinder 20 and piston 23, is provided for normally projecting the cylinder 26 relative to the piston 27.

At its free end cylinder 26 is provided with an intake port controlled by an inwardly opening ball check valve 30. V The cylinders 20 and 26 are connected with a control valve 31, which in the present instance includes an elongated casing mounted between the cylinders 20, 26 and movable therewith. Operating in the casing of the valve 31 is a ball check valve member as clearly shown in Figure 3, and oppositely extending nipples 32, 33 arranged at the ends of the casing of the valve 31 form passages communicating the valve 31 with the cylinders 26, 20 as also clearly shown in Figures 2 and 3. In 0 actual practice lubricant is placed in the reservoir 12 after which the piston 17 is arranged within the reservoir and cap 15 applied to the outer end of the barrel section 10. The nozzle 22 is then placed against the part or element to be lubricated, the barrel of the gun being held in one hand, while with the other hand holding handle 19, the operator forces piston 17 inwardly for. forcing the lubricant from the chamber 12 through the opening in the partition plate 16 :1

intov the charge receiving chamber 13. As the lubricant is thus forced from the chamber 12 into the chamber 13 the barrel of the gun will be caused to move forwardly relative to the discharge mechanism with the result that the cylinders 20, 26 against the action of spring 24 and assisted by the spring 29 move from the position shown in Figure 2 to the position shown in Figure 3. Manifestly this inward movement of the discharge mechanism causes an'expansion'ot'the expansible chamber formed by the cylinder 26 and piston 27 and a contraction of the expandible chamber formed by the cylinder 20 and the piston 23. It will thus be seen that the discharge mechanism is moving inwardly relative to the barrel of the gun or is being retracted at the same time the piston 17 is moving in the direction of the plate 16 with the result that lubricant under pressure passes .through the valve controlledinlet of the piston 26. Whenpressure on the handle 19 is released the spring 24 will'caus'e a projecting of the discharge mechanism, that is to say will cause cylinders 20, 26 to move from the position shown in Figure 2 to the position shown 'in Figure 3. As the discharge mechanism is thus projected piston 27 will act on the lubricant within the cylinder 26 to close the valve 30 and to force the lubricant from the cylinder 26 through the passage 32 into the valve 31, and from the casing of the valve 31 through the passage 33 into the cylinder 20.

When pressure is again exerted on the handle 19 for moving thepiston 1'7 inwardly with reference to the barrel the discharge mechanism will be again retracted, that is to say will again move to the position shown in Figure 3 so that the lubricant forced into the cylinder 20 will become trapped therein by the ball valve element of valve 31 closing. The lubricant thus trapped in the cylinder 20 will, uponthis'retraction of the discharge mechanism and consequent contraction of the expansible chamber formed by cylinder 20, and piston 23 be forced from the cylinder 20 through the nozzle 22 onto the parts to T be lubricated.

Manifestly each time pressure is subsequently applied to handle 19 for forcing the piston 1'7 inwardly lubricant under pressure will be discharged from the gun.

- Even though I have herein shown and described the preferred embodiment of the invention, it is to be understood that the same is susceptible of further changes, modifications and improvements coming within the scope of the appended claims.

Having thus described my invention, what I claim as new is:

by the movement of the piston in the reservoir to deliver a charge of lubricant'to the cylinder to be discharged from the cylinder upon subsequent movement of the fixed piston with the barrel inwardly with reference to the said cylinder.

2. In a lubricating. gun, a charge receiving chamber, and a normally projected discharge mechanism for the gun slidably operating in said chamber and provided with oppositely acting expansible chambers and oppositely acting check valves associated'therewith; one of said chambers expanding to receive a'charge of lubricant,'and the other of said chambers contracting to dispense lubricant therefrom, as the discharge mechanism is retracted; said other chamber expanding to receive a-charge of lubricant and the said one chamber contracting to trap lubricant therein as the discharge mechanism moves to projected position. r

3; A lubricating gun comprising a barrel provided with alubricant reservoir and a charge receiving chamber connected with the reservoir; a'plunger operating in the'reservoir for torcing lubricant from the latter into' the charge receiving chamber; fixed laterally spaced pistons extending inwardly'from relatively opposite ends of the charge receiving chamber an elon gated cylinder slidably mounted in the barrel and having one end projecting outwardly from the barrel and an inner end slidably receiving one of the pistons, a spring engaging the inner end or the cylinder and yieldably urging it outwardly; a relatively short cylinder slidably engaged with 1 the other of said pistons, a spring engaged with said short cylinder urging-it in a direction opposite to the elongated cylinder, an inwardly opening valve controlling thev free end of said short cylinder, a valve establishing and controlling communication between said cylinders and movable '25 therewith; and a discharge nozzle on the outer end of the elongated cylinder.

CLARENCE w. HEFNER. 

